Bi-directional tape transport



May 14, 1968 R. E. SCHROTER 3,383,473

BI-DIRECTIONAL TAPE TRANSPORT Filed Feb. 27, 1965 ll Sheets-Sheet l 157 T 1!? 120 11 M I156 M7 6! r A 7.. 12

62 64 A INVENTOR.

P/a/mep 50/90/75? May 14, 1968 R. E. SCHROTER BI -DIRECTIONAL TAPE TRANSPORT ll Sheets-Sheet 8 Filed Feb. 27, 1965 INVENTOR. flay 92p t? Saaemzee BY M May 14, 1968 R. E. SCHROTER BI-DIRECTIONAL TAPE TRANSPORT ll Sheets-Sheet 4 Filed Feb. 27, 1965 May 14, 1968 R. E. SCHROTER BI-DIRECTIONAL TAPE TRANSPORT ll Sheets-Sheet 5 Filed Feb. 27, 1963 1005 999 996 997 we 995 994 e 225; 997 998 995 EVEN TO START STOP SWITCH YINVENTOR.

2mm 5 Scfleorse Ja aye May 14, 1968 R. E. SCHROTER BI-DIRECTIONAL TAPE TRANSPORT ll Sheets-Sheet 6 Filed Feb. 27, 1963 GOA/7801 417 4/6 INVENTOR.

BY [Q251 9&4 ,a/mzf 4rraeA/E K5 May 14, 1968 R. E. SCHROTER BI-DIRECTIONAL TAPE TRANSPORT ll Sheets-Sheet 7 Filed Feb. 27, 1963 IN V EN TOR. 0679480 E a/eoree 1d 242%]: 477'0eA/5 *5 ay 14, 1968 R. E. SCHROTER 3,383,473

BIDIRECTIONAL TAPE TRANSPORT Filed Feb. 27, 1965 ll Sheets-Sheet 8 y 4, 1968 R. E. SCHROTER 3,383,473

BI-DIRECTIONAL TAPE TRANSPORT Filed Feb. 27, 1963 ll Sheets-Sheet 9 l/ckmeo Sal /gorse MW 4%; M 24%:

y 4, 1968 R. E. SCHROTER 3,383,473

BI-DIRECTIONAL TAPE TRANSPORT F le Feb- 2 3 ll Sheets-Sheet l0 INVENTOR ,/o-mea f. .Qwwzze May 14, 1968 R. E. SCHROTER BI-DIRECTIONAL TAPE TRANSPORT Filed Feb. 27, 1963 ll Sheets-Sheet 11 INVENTOR. 50/420 4. 564202222 1 Ei WW United States Patent 3,383,473 BI-DIRECTIONAL TAPE TRANSPORT Richard E. Schroter, Hollywood, Calif., assignor to Ralph J. Samuels, Los Angeles, Calif.

Continuation-impart of application Ser. No. 803,490,

Apr. 1, 1959. This application Feb. 27, I963, Ser.

12 Claims. (til. 179-1002) This application is a continuation-in-part of my copending application, Tape recorder and Reproducer, Ser. No. 803,490 filed Apr. 1, 1959, and now abandoned.

As is well known, prior art tape recorders have long been criticized as being unduly bulky and heavy, or undesirably expensive to produce, or both. Many attempts have been made in the past to develop miniature tape recorders, but it has generally been found that the smaller tape recorders having the recording and reproducing qualities of larger ones cannot be made Without resort to unduly expensive and complex circuits and components.

Prior attempts to provide compact tape recorders have resulted in failure to produce one utilizing a short length of tape and having the recording time of larger recorders, and still characterized by extreme simplicity of design and economy of manufacture. In short, what has been lacking is a tape recorder to fill the demands of consumers for an inexpensive, small, lightweight, high quality tape recording unit with which recording time is comparable to that of the presently known bulky recorders.

Tape recorders as heretofore known have generally been unsatisfactory for the recording and reproduction of music, in spite of the fact that tape is recognized as a superior medium to phonograph records for the recording of music. One reason is that the tape must be handled, and in the process becomes soiled and is subjected to tearing or other deformation which results in an impairment of the continuity or quality of music reproduced therefrom. And high quality music reproduction has been non-existent in miniature recorders using short lengths of tape, a result which in part occurs from the dilemma of required high tape speeds for music.

It is an object of this invention to provide an improved magnetic tape recorder which overcomes the above and other disadvantages of prior art tape recorders.

Another object of this invention is to provide an im proved tape recorder which is smaller in size and lighter in weight than prior art tape recorders, yet which provides as much playing time as can be realized with large and unwieldly reels of tape.

A further object of this invention is to provide an improved tape recorder of small and compact size which utilizes removable cartridges of magnetic tape, wherein the tape never has to be handled in any manner.

It is a further object of this invention to provide an improved tape recorder utilizing a small removable cartridge of magnetic tape, in which multiple lane recording is utilized to provide recording time comparable to that obtained heretofore only with large and unwieldly reels of tape.

An additional object of this invention is to provide a tape recorder having a removable tape cartridge which is self-locating on the main housing of the recorder so as to be automatically positioned for operative engagement with drive means for the tape.

A still further object of this invention is to provide an improved tape recorder which utilizes a single recording head for multiple track recording on the same surface of a width of tape, and wherein any portion of any track can be rapidly and positively located adjacent the head.

Still another object of this invention is to provide a unique electro-mechanical structure for relatively shifting the position of the recording head transversely along a 3,383,473 Patented May 14-, 1968 magnetic tape for recording sounds along multiple lanes of the tape.

An additional object of this invention is to provide a unique miniature tape recorder which uses a short length of tape but is still capable of high quality recording and reproduction of music at high tape speeds.

The above and other objects and advantages of this invention will become apparent from the following description taken in conjunction with the accompanying drawings of illustrative embodiments thereof; in which:

FIGURE 1 is a perspective view of one embodiment of a tape recorder having a plug-in tape cartridge in accordance with my invention;

FIGURE 2 is a sectional view of the recorder of FIG- URE 1, showing the means for operating the tape and the record-listen and erase heads;

FIGURE 3 is a sectional view taken along the line 3-3 of FIGURE 2, showing the relative positions of the reels and the capstan in the cartridge, and the positions of the record and erase heads against the tape;

FIGURE 4 is a sectional view taken along the line 44 of FIGURE 2, showing normal and high speed drive motors, and showing the main control shaft having both manual and electromechanically actuatable means for effecting its rotation to move the record-listen and erase heads, and also showing the arrangement of cams on the control shaft utilized for controlling the direction of rotation of the capstan;

FIGURE 5 is an end elevation view of the flywheels used for the capstan drive, showing their interconnection for operation in opposite directions;

FIGURE 6 is a fragmentary sectional view taken along the line 66 of FIGURE 5, showing how the shaft on which the flywheel is mounted is adapted for rotation in its movable support;

FIGURE 7 is a side elevation view taken along the line 77 of FIGURE 2, showing the arrangement of a contact and contact element for use in controlling the electrical operation of the erase heads;

FIGURE 8 is an exploded view of the parts of the contact of FIGURE 7;

FIGURE 9 is an end elevational view taken along the line 99 of FIGURE 2, showing a contact element cooperatively related with respective contacts affixed to the housing for effecting reversal of the direction of the tape with the high speed motor;

FIGURE 10 is a fragmentary sectional view taken along the line lit-10 of FIGURE 4, showing the shape of the cam elements used in conjunction with the drive shafts for operating the capstan drive;

FIGURE 11 is a fragmentary sectional view taken along the line 11--11 of FIGURE 4, showing the snap action detent arrangement for positively locating the record-listen and erase heads in the center of a track;

FIGURE 12 is a fragmentary sectional view taken along the line 12-12 of FIGURE 2, showing the construction of the reels or spindles employed in the cartridge;

FIGURE 13 is a sectional view taken along the line 1313 of FIGURE 12, showing how the end of a coil spring for tensioning the tape is removably secured to the interior of a spindle;

FIGURE 14 is a perspective view of the tape plug-in unit, partially broken away to show the disposition therein of the reels and the capstan, and showing the locating pins on the ends of the shaft on which the reels are mounted for insuring the proper positioning of the plugin unit of the main housing;

FIGURE 15 is a fragmentary sectional view of the solenoid-operated rack and pinion structure for rotating the main control shaft to shift the record-listen and erase heads at the end of each track on the tape, and showing (3 the disposition of the ratchet detent structure for controlling the direction in which the main control shaft is turned;

FIGURE 16 is a fragmentary sectional view of the capstan, showing the location at one end of a metal portion to be exposed for contact at the end of a track for effecting energization of the solenoid;

FIGURE 17 is a fragmentary plan view of the tape, showing how it is partially cut away at the sides adjacent its ends to insure that the metal portion of the capstan will be exposed at the proper moment for shifting the record-listen and erase heads;

FIGURE 18 is a fragmentary top plan view of the solenoid-operated mechanism for stop-start control, and showing a ratchet and cam mechanism for manual stopstart control;

FIGURE 19 is an enlarged end view of the ratchet and cam mechanism of FIGURE 18;

FIGURE 20 is a combined schematic and block diagram of electrical control means for synchronizing the desired operations of the motors, the tape, and the recordlisten and erase, heads;

FIGURE 21 is an elevational view taken along the line 21-21 of FIGURE 20, showing how the rotatable contact elements are arranged for alternately connecting the erase heads to the erase current source;

FIGURE 22 is .a fragmentary plan view of the tape numbered so as to aid the operator in determining the direction of travel thereof;

FIGURE 23 is an enlarged top plan view of the tape cartridge, showing window openings to permit the operator to see the number indications;

FIGURE 24 is a fragmentary plan view of a capstan and tape arranged for moving the tape by sprocket drive;

FIGURE 25 is a schematic diagram of coin-operated control means for operating a music reproducing unit;

FIGURE 26 is a perspective view of another embodiment of a completely self-contained, pocket-sized tape recorder of my invention, showing the accessibility of various controls externally of the housing for operating the drive mechanism, the magnetic heads, and the electronic system contained therein;

FIGURE 27 is a top plan view of the interior of housing, showing the arrangement of the drive mechanism and magnetic head controlling mechanism, and showing the detachable cartridge in position;

FIGURE 28 is a sectional view taken along the line 28--28 of FIGURE 27, showing the arrangement of the output shaft of the motor drive for rotating the shaft of the drive mechanism, and showing the operable positions of the motor On-Off switch control lever;

FIGURE 29 is a sectional view taken along the line 2929 of FIGURE 27, showing the arrangements of the gears that cooperate in the positioning of the magnetic head, and showing the rewind spring mechanism for the central control member located below the housing;

FIGURE 30 is a sectional view taken along the line 3030 of FIGURE 27, showing arrangements of the driving shaft, the main control member, and the rocker arm for controlling the position of the driving shaft;

FIGURE 31 is a fragmentary top plan view of the driving shaft and the rocker arm, and showing in section the portion of the main control member which determines the position of the rocker :arm and the driving shaft;

FIGURE 32 is a fragmentary side elevational view of the rocker arm and the cooperating portion of the main control member;

FIGURE 33 is a fragmentary side elevational view of the portion of the main control member that determines the lateral position of the rocker arm;

FIGURE 34 is a perspective view of the tape-operated levers by which to automatically change the position of the magnetic heads;

FIGURES 35 and 36 are fragmentary top plan views of the main portions of the driving mechanism for the tape, and showing the actuation of the switch by the main control member for synchronously operating erase heads with the recording and playback head with the direction of movement of the tape, so that pro-recorded sounds are erased immediately preceding the recording of new sounds thereon;

FIGURES 37 and 38 are fragmentary top plan views, partly broken away, of the main portions of the tapeoperated head shifting controls, showing an example of one of the levers being engaged by the tape adjacent one end thereof, and carried to a position to effect movement of the heads a predetermined distance transversely of the tapes;

FIGURE 39 is a perspective view of a tape cartridge construction of my invention, showing the central opening through the housing to permit it to be slipped over the magnetic heads so they engage the tape, and showing openings on the top of the housing for permitting the levers to engage the tape;

FIGURE 40 has a sectional view taken along the line 40-40 of FIGURE 39, showing more clearly the interior construction of the cartridge housing;

FIGURE 41 is a sectional view taken along the line 4141 of FIGURE 40, showing the arrangement for locating and holding the tape-supporting spools in the cartridge housing;

FIGURE 42 is an enlarged, fragmentary sectional view of the slotted end portion of the tape, with the end of a lever in position wherein it is engaged by and carried with the tape;

FIGURE 43 is a top plan view of the tape, with lines indicating diagrammatically the forward and reverse directions of movement of the tape, to aid in explaining the operation of the system of my invention;

FIGURE 44 is a schematic diagram of the circuit for controlling the operation of the erase heads;

FIGURE 45 is a perspective view of another tape cartridge embodying my invention, showing a pair of guide openings in the cartridge casing to receive externally operated capstans;

FIGURE 46 is an exploded view of the parts of the cartridge of FIGURE 45;

FIGURE 47 is a side elevation view of the cartridge, showing the cam surface portions for guiding the capstans into parallel alignment;

FIGURE 48 is a fragmentary sectional view taken along the line 48-48 of FIGURE 47;

FIGURE 49 is a longitudinal sectional view of the cartridge of FIGURE 45, showing a pair of capstans in position to be cammed into parallel alignment by the cartridge as it is fitted onto a housing; and

FIGURE 50 is a view similar to FIGURE 49 in which the cartridge has been moved into place for recording and reproduction, and the capstans are in parallel alignment for driving the tape.

Referring to FIGURE 1, there is shown a recorder housing It) on which is mounted a plug-in tape cartridge 11. Operation of the recorder is controlled from a hand set 12 which is electrically connected, as at 13, to the housing 10. The hand set 12 is provided with control buttons 14, 15, 16 for use in starting and stopping the capstan, controllin the direction of travel of the tape, and for selectively recording and playing back sounds on the tape. The hand set 12 is provided with a combination microphone and speaker arrangement, which may be of conventional design, for record and playback purposes. Additionally, the hand set 12 houses amplifier means for networks used in conjunction with the recording and playback operations.

Referring to FIGURES 2, 3 and 12-14, the cartridge 11 comprises a casing 20 in which is rotatably mounted a pair of reels 21, 22. Mounted on the reels 21, 22 :is a magnetic tape 24 which at its ends is secured to the reels. Rotation of the reels 21, 22 is effected by the tape 24, and to this end the tape 24 is looped or passed around a capstan plug 25 which is rotatably mounted within the casing 20. The shaft 26 of the capstan 25 extends from the casing 28 into the interior of the housing where it is engaged for rotation. Rotation of the capstan in either direction causes the tape 24 to travel around the capstan.

When the cartridge 11 is plugged into the housing 10, an assembly of a record-listen head 38 and a pair of erase heads 31, 32 supported from within the housing are positioned so as to engage the tape 24 (see FIGURE 3). The heads -32 are in fixed spaced relation to each other, as by being embedded in a bar 33 of insulating material, as shown. The bar 33 is pivoted at one end, as at 34, to a bracket 35 which is adapted for movement transversely of the tape 24.

With the above described arrangement, I utilize multiple lane recording, whereby with miniature size reels and short length of tape, I obtain an effective recording and playing time comparable to that heretofore obtainable only with large bulky reels and considerable tape footage.

This is effected by rotating the capstan 25 in one direction so that the tape passes over the heads 3G32 in one direction, shifting the heads 30-32 transversely of the tape at the end thereof and reversing the rotation of the capstan 25 to cause the tape to pass over the heads in the opposite direction.

With this compact arrangement of reels of the size of spools used for thread, I am able to obtain an effective tape length and playing time comparable to that heretofore obtained with seven-inch reels. This is accomplished, with a tape of given length and width, by the use of heads 30-32 which are sufliciently narrow that they can be shifted incremental distances along the width of the tape, so that the total tape footage passing the heads is equal to the footage heretofore obtainable only with extremely large reels. For example, with a thirty-foot length of tape, which is one inch wide, and heads 3'932 no wider than 0.025 inch, forty parallel tracks are provided; thus, 1200 feet of tape traverse the heads as they are moved from one edge of the tape to the other.

It will be recognized that as the tape 24 transfers from one reel to the other, the reels will be operating at different speeds of rotation. hi this embodiment, in order that the tape be maintained in tension at all times, I employ a unique construction and arrangement for rotatably supporting the reels 21, 22, in the manner shown in FIG- URES 2 and 12l4.

As shown, the reels are mounted on a non-rotatable U-shaped rod 38, which has threaded ends extending through the inner panel 39 of the casing 20. A pair of nuts 40 are threaded onto the ends of the shaft 38 to abut the panel 39. The reels (see FIGURES 12 and 13) comprise cylindrical elements 41 having radial rims or flanges 42, and are rotatably mounted on the ends of the rod 38 by means of sleeve elements 44. The elements 44 are freely rotatable on the rod.

To prevent the reel from moving along the rod 38, a collar 45 is secured to the rod 38 so as to abut the end of the sleeve 44 remote from the front panel 39. Thus, the reel is located between the collar 45 and the plate 39. To additionally facilitate rotation of a reel, a Washer 46 is disposed between the plate 39 and the adjacent end of the sleeve 44. v

The means for maintaining the desired tension abovementioned is a coil spring 47 which encircles the shaft 38 between the reels. The ends 48 of the spring 47 (see FIGURES 12 and 13) are releasably held to the reels, as by being disposed in a longitudinal slot or groove 49 provided in the inner surface of the cylinder 41. To eflect the desired tension, all that is necessary is to rotate one reel relative to the other to build up tension in the spring 47. After thus preloading one reel with respect t the other, the reels are located on the plate 39, the threaded ends of the shaft extending through such plate to be secured in place by the nuts 40. In this manner, both of the reels are under tension.

The number of turns or twists of the spring 47 is dependent on the differential effect needed. This in turn is based upon considerations of such factors as the ratio of the total diameter of the cylinder and tape to the diameter of 'the cylinder 41, the length of the spring 47, and the thickness or diameter of the turns of the spring.

Regardless of the position of the tape, i.e., the relative thicknesses thereof of the two reels, the reels are always under tension. Also, it is by virtue of the tape being on the reels, and of the U-shaped arrangement of the spring 47, that the preloading of the spring will be maintained when the reels are located in place. Thus assembled, as the spring undergoes tension in either direction, it will be distorted on the shaft 38. This is a form of kinking, but the spring is made sufficiently long so that it cannot undergo a secondary form of twisting or kinking. At dead center, where the tape is of the same thickness on each reel, and the speeds of the reels are momentarily the same, the tension of the spring 47 is at its lowest point; however, there is still suflicient tension in the spring at this mid-point to keep the tape taut.

Another advantage of the tensioning is that the tape is kept taut against the capstan 25. This means that the tape 24 inherently is in frictional engagement with the capstan 25, so that the use of a frictional surface material for the capstan is suflicient to insure movement of the tape as the capstan is turned, i.e., to prevent relative slippage between the tape and the capstan surface.

If desired, additional safeguards may be provided to prevent relative slippage between the tape and the capstan. To this end, a spring-biased pressure roller 50 (See FIGURES 2 and 3) may be employed. As shown, the roller 50 is rotatably mounted on the lower end of a bracket 51, and is biased by a spring 52 so as to be urged against the capstan 25. The roller 50 is provided with a surface covering 53 of resilient material, so as not to mar the tape. The bracket 51 is pivotally mounted at 54, and a stop 55 on the housing 10 is disposed in the path of the upper end of the bracket 51 so as to limit the pressure engagement of the roller surface 53 with the capstan 25.

For effecting rotation of the capstan 25 in either direction, I provide a unidirectional motor (see FIG- URE 2) having a short, flexible output shaft 61. The flexible shaft 61 is adapted to drive a rigid shaft element 62, and for this purpose an elongated sleeve or collar 63 is placed over the ends of the shaft elements 61 and 62.

The rigid shaft element 62 is provided with a grooved collar 64 to receive a belt 65. The belt 65 forms a drive connection to a flywheel element 66 (see FIGURES 5 and 6) which is secured to a shaft 67 that is freely rotatable in bearings 68, 69 in a sleeve 70 which extends from a plate 71 on the bottom of the housing 10.

Spaced from the plate 71 is a similar plate 72 (see FIGURES 2 and 5) having a tube 73 in which another shaft 74 is rotatably mounted, such shaft 74 having a flywheel 75 secured thereto.

The flywheels 66, 75 are connected by a flexible shaft 76, the ends of which (see FIGURE 6) are connected to the ends of the shafts 67, 74. With this arrangement, it will be seen that rotation of the shaft 62 by the motor 60 will effect rotation of the flywheels 66, 75, and hence the shafts 67, 74, in opposite directions.

The oppositely rotating shafts 67, 74 are utilized t drive the capstan 25. This is accomplished by means of a drive wheel 78 which is rotatably supported, as on a bracket 79, and which has a shaft 80 for driving the capstan 25. The drive wheel 78 is extremely light in weight, so as to have negligible inertia, and its diameter is many times that of the drive shafts 67, 74. For lightness, the wheel 78 may be made of aluminum or plastic.

To effect the driving connection between the shaft 80 and the end 26 of the capstan 25, the shaft 80 is pro vided with a split-end sleeve 31 which extends to an opening 82 in the housing which is aligned with the axis of the capstan when the cartridge 11 is in position. The sleeve 81 preferably is formed of spring metal, and the split ends thereof are spaced apart a distance less than the diameter of the shaft 26 extending from the capstan 25, so that the shaft 26 must force the split ends of the sleeve end apart when the cartridge 11 is plugged into position. By this means, the split ends of the sleeve 81 grip the shaft 26, so that turning of the shaft will result in turning of the capstan 25.

Rotation of the drive wheel 73 is effected through the shafts 67, 74. For selectively connecting the shafts 67, 74 for driving the drive wheel 78, the plates 71, 72 are pivotally mounted within the housing 10. Referring to FIGURES 2 and 4-6, the plates 71, 72 are shown to extend upwardly from flat plate element 85, 86 which are slidahly disposed on the bottom or floor of the housing 10, on which they are pivotally mounted at one end, as

at 87, S8. The plates 85, 86 are biased toward one another, as by a spring 39 connected between the free ends thereof.

Referring to FIGURE l8 along with FIGURES 2 and 4-6, the plates 85, 86 are provided with confronting projections 90, 91. The projections 90, 91 constitute cam follower elements which facilitate movement of the plates 85, 86 so that one or the other of the shafts 67, 74 engage the drive wheel 88. To this end, a main control shaft 95 extending the width of the housing 10 is provided with a pair of cam elements 96, 9-7 which are located between the plates 85, 86 the axis of the shaft 95 being parallel to the line between the cam follower projection-s 90, 91 on such plates.

Referring to FIGURE 10, the cam elements 96, 97 are identically shaped. In the configuration shown, the cam element 97 is of generally cruciform shape having teeth of such size that the space between adjacent teeth is substantially the same distance as the width of the teeth.

The cam elements 96, 97 are mounted on the shaft 95 so that the teeth of one are aligned with the space between adjacent teeth of the other. Further, the radial distance from the center of the shaft 95 to the perimeter of the teeth of the cams is greater than the distance between the shaft 95 and the upper surfaces of the plates 85, 86. When any tooth of any cam is located on the line between the projections 90, 91, such line is straddled by adjacent teeth on the other cam. Furthermore, the earns 96, 97 are so spaced that the projections 90, 91 are always in the path of one of the teeth thereof. Accordingly, by virtue of the tension of the spring 89, tending to draw the plates 85, 86 together, rotation of the shaft 95 causes the plates 85, 86 to pivot in parallel.

The distance between the shafts 67, 74 is such that, when a cam element, for example, the cam 97, engages the associated cam follower projection 91 on the plate 86, the plate 86 is moved away from the drive wheel '78, and the other plate 85, due to the action of the spring 89, is moved toward the drive wheel 78. This separates the shaft 74 from the drive wheel 78, and places the shaft 67 in contact with the drive wheel. Opposite movement takes place when the shaft 95 rotates to place the opposite cam 96 in engagement with the associated cam follower projection on the plate 85; the shaft 67 moves out of engagement with the drive wheel 78, and the shaft 74 is moved into engagement with the drive wheel.

Due to the relatively inertia-1ess character of the drive wheel 78, no slippage occurs upon its being suddenly engaged by one of the shafts 67, 74 to reverse it direction of rotation. Thus, the reversal of the drive wheel is substantially instantaneous, a factor which, as will be seen, insures continuity of recording upon reversal of the tape.

Initially, substantially all of the tape 24 is on one of the reels, e.g., the reel 21. The capstan 25 is rotated in a direction to feed the tape over the heads 3032 and onto the other reel 22. When substantially all of the tape is on such other reel 22, the capstan 25 is automatically reversed, and the bracket 35 is simultaneously shifted transversely a distance of one track. When the tape again is on the reel 21, the capstan again reverses to feed it back to the reel 22, and the bracket is again shifted over one track. These operations-reversal of the tape and shifting of the heads 3032occur simultaneously, in a manner now to be explained.

Referring to FIGURES 2 and 4, a pinion 1100 fixed on the shaft meshes with the teeth on a rack 101 which is supported on the bracket 35. The bracket 35 at its inner end carries a rectangular compartment 102 in which the rack 101 is located. Thus, when the shaft 95 is turned, the pinion turns against the rack 101 to urge it longitudinally. Depending on the direction of such movement, the rack 101 is forced against one end of the compartment 102. The bracket, which is slidable along the base of the housing 10, is thus moved upon rotation of the pinion, thereby shifting heads 30-32 transversely of the tape 24.

Guide means are provided for the bracket 34, in the form of a pair of pins 104 (see FIGURE 2) on either side thereof, a slot or keyway 105, and a pin 106 (see FIGURE 4) on the bottom of the bracket which is slid- .a-ble in the slot 105. Upon the bracket 35 being moved by the action of the pinion 100, it slides between the pins 164. The pins 104 and the pin 106 and slot cooperate to prevent lateral movement of the bracket.

The rack and pinion arrangement in this embodiment employs unique anti-backlash means. Referring to FIG- URE 4, the rack 101 rests on a cushion 1.07 in the compartment 102. The cushion 107 is made of resilient material (e.g., foam rubber), against which the rack 101 is urged by the pinion 100. The rack 101 is free to move or rock longitudinally in the compartment 102. When the pinion forces the rack longitudinally, the constant upward pressure exerted by the cushion 107 prevents play between the rack and pinion elements.

To effect operation of the pinion 100 for moving the bracket 35 and the heads 30-32 transversely a distance of one track or lane, the shaft 95 is rotated by a mechanism which includes a ratchet wheel 108 secured thereto (see FIGURES 2 and 15) and a pawl assembly 109 operated by a solenoid 110 (see FIGURES 2 and 4).

The pawl assembly 109 includes a vertical plate 111 (FIGURE 15) which is pivotally connected at one end to a spring-biased plunger 112 of the solenoid 110. The plate 111 is disposed on one side of the ratchet wheel 108, and has an elongated slot 113 to receive the shaft 95 and to permit its movement transversely of the shaft. Above and below the ratchet wheel 108, the plate 111 has a pair of horizontal legs 114, 115 (see FIGURE 4) which are curved at their inner ends (FIGURE l5) toward the ratchet wheel, as at 116, 117. A pair of springs 113, 119 are connected between the upper corners of the plate 111 and the adjacent end of the housing 10.

The plate 111 is positioned so that when the solenoid 110 is actuated, one of the curved ends 116, 117, which constitute pawls, will engage the ratchet wheel 10?, to thereby force the shaft 95 and pinion 100 to rotate and move bracket 35 longitudinally. The positioning of the plate is effected through a lever 120 which is pivoted on the side of the housing 10, as at 121, and from which a finger 122 extends through the slot 113. The lever 120 has two positions-a forward position, in which the finger 122 holds the plate in an upper position where the lower pawl. 117 is against the ratchet wheel 108, and a rearward position, in which the finger 122 holds the plate down so the upper pawl 116 is against the ratchet wheel.

The plunger 112 normally is in an outer position. When the solenoid 110 is energized, the plunger 112 and plate 111 are moved longitudinally, and the operative pawl 9 thereby forces the ratchet wheel 108 and the shaft 95 to turn. It should be noted (see FIGURE that both sides of the teeth of the ratchet wheel 108 are substantially radial, whereby the ratchet wheel can be moved readily clockwise or counterclockwise by the pawls 116, 117.

My invention effects energization of the solenoid 110 automatically at the end of each recording track. To this end, a D-C source 124 (see FIGURE which may be provided by batteries 125 as illustrated in FIGURE 4, is utilized to energize the solenoid 110. The solenoid is connected between the D-C source 124 and a leaf spring contact element 126 (see FIGURES 3, l6, and 17 along with FIGURE 20).

The contact element 126 is secured at one end to the housing 10, as shown at 127, and at its other end is urged against the capstan 25. Such movable end of the contact 126 normally is separated from the capstan by the tape 24. However, the tape adjacent its ends is partially cut away on one side, as indicated at 128, with which the contact 126 is aligned. When such portions 128 appear at the capstan 25, the contact 126 is free to move inwardly and engage the capstan 25.

The portion of the capstan 25 engaged by the contact 126 is metallic, as indicated at 129. This forms a ground connection to the housing through the capstan 25, the drive shaft 80 and bracket 79. This completes the connection of the solenoid across the source 124, whereupon the solenoid 116 is energized to effect movement of the bracket and the heads 33-32 as previously described. As shown in FIGURE 16, the remainder of the capstan 25 between its ends is covered by a sleeve 130 which frictionally engages the tape and minimizes slippage between the tape and the capstan in the manner previously indicated.

Recording on all the available tracks is effected by setting the bracket 35 so that the heads 30-32 are positioned at one edge of the tape 24, e.g., the outer edge as shown in FIGURE 2. Thereafter, the bracket is shifted, one track at a time on each reversal of the capstan 25, until they reach the opposite edge of the tape. Further, the erase heads 31, 32 are selectively operated in accordance with the direction of travel of the tape. Referring to FIG- URES 3 and 20, when the tape'24 is traveling from left to right, the erase head 31 which is ahead of the record head is adapted to clear the tape. When the tape is traveling from right to left, erase current is supplied to the erase head 32 ahead of the record head 30.

The electronic networks for recording and listening are shown in FIGURE 20. These include a preamplifier 132, a record amplifier 133, a playback amplifier 134, and an erase current source 135. The erase current source 135 may be either a DC source, in which case it is located in the housing 10 (and may constitute the batteries 125), or an AC source such as an oscillator, which is located in the hand set 12 along with the amplifiers 132, 133 and 134. The circuits employed are conventional, and are preferably composed of miniature components, such as are effected with transistor devices, so they are readily incorporated in a hand set of reasonable size.

The input of the pre-amplifier 132, the outputs of the record and playback amplifiers 133, 134, and the output of the erase current source 135 are connected to the switch arms of respective single-pole, double-throw switches 136, 137, 138, 139, which are ganged as indicated at 140. The switch 136 in one position connects the input of the pre-amplifier 132 to the microphone 141, and in the other position connects such input to the recordlisten head 30, through connections 142 and 143. The switches 137, 138, 139 each have one dead position. In their other positions, the switch 137 connects the output of the record amplifier 133 to the record-listen head 30, through connections 144, 143, the switch 138 connects the output of the playback amplifier 134 to the loudspeaker 146, and the switch 139 connects the erase current source 135 to the erase heads 31, 32 (in a manner to be described more fully hereinafter).

The switches 136-139 are so arranged that the record amplifier 133 and the erase current source 135 are connected to the record-listen head 30 and the erase heads 31, 32 when the pre-amplifier input is connected to the microphone 141, in which case the switch 138 is in its dead position. When the switches are moved to connect the playback amplifier 134 to the loudspeaker 146, the switches 137, 139 are connected to their dead positions, and the switch 136 connects the input of the pre-amplifier 132 to the record-listen head. Respective connections 147, 148 are provided between the pre-amplifier 132 and the record and playback amplifiers 133, 134 to effect recording or playback of sounds in accordance with the switchmg.

To supply erase current to the erase head which is ahead of the record-listen head, I utilize a switch assembly mounted on the shaft 95. Referring to FIGURES 2, 4, 7, 8, 20, and 21, such switch assembly comprises a pair of conductive elements 149, 150 separated by a disc 151 of insulating material (FIGURES 7 and 8). The conductive elements 149, 150 are secured to the insulating disc 151 in such a way as to be insulated from each other, e.g., as by bolts 152 extending through each element into the disc 151, the bolts in one element being nonaligned with those in the other. The disc 151 is secured to the shaft 95, but the elements 149, 150 do not touch the shaft, by virtue of central openings 154, 155 therein which are of greater diameter than the shaft.

A leaf spring contact element 156, the width of which is greater than the thickness of the insulating disc 151, is secured to the housing (see FIGURES 2 and 7), as at 157, with the free end thereof spanning the disc 151. The elements 149, 150 are shaped and oriented so that the contact 156 engages them alternately as the shaft rotates.

The contact 156 (see FIGURES 20 and 21) is connected, as at 158, to the switch 139, and the respective conductive elements 149, 150 are engaged by brush contacts 160, 161 which are connected to the erase heads 32, 31 through respective connections 162, 163. Thus, rotation of the shaft 95 to alternately connect the elements 149, 150 to the contact 156 results in the erase heads 31, 32 being alternately connected to the erase current source 135.

The elements 149, 150 rotate in unison, so that each time the shaft 95 is turned by the solenoid to shift the positions of the heads 30-32 and the direction of rotation of the capstan is reversed, the erase current source is disconnected from one erase head and conductively connected to the other. The elements 149, are positioned so that, as the tape 24 moves from left to right, the contact 156 is in engagement with the element 150, and as the tape moves from right to left, the contact 156 is in engagement with the element 149. Thus, in the recording phase, the tape 24 is always erased before it passes over the record-listen head 30.

A master on-off switch 165 is provided for supplying power from the source 124. When the switch 165 is closed, the motor 60 operates continuously. However, I provide means for selectively coupling and decoupling the drive wheel 78 at any time from the one of the shafts 67, 74 which is driving it. Referring to FIGURES 2, l8, and 19, this starting and stopping of the drive wheel 78, and hence the capstan 25, is effected through a solenoid 166 having a spring-biased plunger 167 located adjacent the bottom of the housing 16.

The plunger 167 extends through a flat plate 168 which is disposed between the plates 85, 86. When the solenoid 166 is energized, the plate 168 is pulled by the plunger 167. The plate 168 is shaped so as to spread or cam the plates 85, 86 apart sufficiently so that neither of the shafts 67, 74 is in engagement with the drive wheel 78. The next time the solenoid 166 is energized and the plunger 167 is pulled back, the plate 168 releases the plates 85, 86 to permit the spring 89 to urge them together to as sume the positions they occupied previously. Since the shaft has not moved, the cams 96, 97 are in the same positions, so that this result will obtain automatically.

Referring to FIGURE 20, this coupling and decoupling of the drive wheel 73 is controlled by the start stop switch 14, which is connected from the handset 12 (FIG URE l) to the source 124 and the solenoid 166, as indicated at 17 171.

Again referring to FIGURES 2, l8 and 19, the ar rangement illustrated for forcing the plates 35, 86 apart includes lateral cam follower projections 1'72, 173 on the plates 85, 86. The plate 168 constitutes a cam having lateral projections 174, 175 which are adapted to engage the projections 172, 173 when it is actuated by the solenoid 166.

To hold the cam plate 168 in the position where it forces the plates 85, 86 apart, on one closure of the switch 14, and to release it on the next closure of the switch 14, there is provided a ratchet, cam and detent mechanism in the form of a cup element 176 having spaced notches or cut-out portions 177 along the skirt thereof. A pawl or detent element 173 is pivoted intermediate its ends and is biased at one end, as by a spring 179, to ride against the rim of the cup 176. Upon rotation of the cup, the spring-biased end of the detent 178 acts as a cam follower, following the contour of the rim. The detent 178 is bent, as shown, so that its other end rocks up and down.

The cam plate 163 is provided with a notch 180. When the cam plate 163 is retracted to decouple the drive to the 2 drive wheel 78, the spring-biased end of the detent 178 is arranged to enter a notch 177 in the cup 176, and its other end enters the notch 18% of the cam plate 168. The cam plate is thus locked in the retracted position. On the next succeeding closure of the switch 14, the cup 176 is rotated to force the detent 178 out of the notch 180 and free the cam plate for return to its normal position for permitting the drive wheel 78 to be driven.

To effect rotation of the cup 176, ratchet wheel 181 is secured to the upper surface thereof. The plunger 167 is provided with an L-shaped arm 182 on which is mounted a pawl 183. Whenever the plunger 167 is retracted, the pawl 1S3 engages a tooth of the ratchet wheel to rotate the cup 176. The cup 176 is held against reverse rotation by a detent finger 184 which is pivo-tally mounted on the housing 10, as at 185. The finger 184 is biased, as by a leaf spring 186, so that it is always urged against the ratchet wheel 181.

In addition to the start-stop and record-listen controls previously described, my invention also incorporates a unique high-speed drive. Referring to FIGURES 2 and 4, there is provided a high speed motor 187 having a flexible output shaft 188 on which is secured a sleeve 89. The sleeve 18% extends through the upper end of a vertical arm 190 which extends from a cam follower plate 191 pivotally supported, as at 192, on the base of the housing 10. A spring 193 extends between the arm 190 to an arm 194 that is fixed at its lower end to the base of the housing. The spring 193 is in tension, so as to constantly urge the movable arm 190 toward the fixed arm 194.

On the end of the sleeve 189 is an enlarged drive head 195, preferably having a frictional surface, which is located adjacent the periphery of the drive wheel 78. The cam follower plate 191 has a projection 196 which normally abuts a projection 197 on the cam plate 168. When the cam plate 168 is retracted, the projection 197 moves past the projection 196, whereupon the plate 191 is freed to move under the action of the spring 193. Such movement of the plate 191 places the drive head 196 in engagement with the periphery of the drive wheel. Thus, the highspeed motor shaft is connected to the drive wheel '73 simultaneously with the separation of the shafts 67, 74 therefrom.

Upon release of the cam plate .168 to return to its normal position under the action of the plunger 167, the projection 197 is forced back to its normal position, thereby to move the plate 191 and separate the drive head from the drive wheel.

Thus, any time the start-stop switch 14 is actuated to disconnect the shafts 67, 74 from the drive wheel, i.e., to stop recording or playback, the drive wheel is set up for high speed operation. Referring to FIGURE 1 and 20, operation of the high speed motor 187 is effected through the switch button 16, which controls a doublepole, double-throw switch having switch arms 20! 20.1 movable from a neutral position to positions F and R for controlling the direction of movement of the tape and the heads 30-32. The switch button 16 may be of sliding latch type, capable of remaining in the F or R position to which it is moved. Movement of the switch button 16 in one direction connects the switch arms to the F contacts 202, 203; sliding the push button in the opposite direction connects the switch arms to the R contacts 204, 205.

The switch cams 200, 201 are connected to the brushes of the motor 187, as at 206, 207. The F contact 262 and R contact 205 are directly connected, as at 208, and the remaining F contact 203 and R" contact 204 aredirectly connected, as at 209. These switch connections are operable to effect successive movements of the heads 39-32 in one direction along the tape 24 when the switch arms 2%, 201 are in the R positions, and in the opposite directions when they are in the F positions. How this is accomplished will now be explained.

The F contacts are connected, as at 210, 211 (FIG- URE 20), to respective leaf spring contact elements 212, 213. The contact elements 212, 213 engage a switching device secured to the shaft 95 which comprises conductive elements 214, 215 (FIGURE 9) separated by an insulating disc 216, such conductive elements 214, 215 being arranged and shaped as the conductive elements 149, 150 previously described for connecting the erase heads 31, 32 to the erase current source 135.

The contact elements 212, 21.3 are both wider than the insulating disc 21.6. The conductive elements 214, 215 each have equally spaced notches along their peripheries, and are arranged so that the notches are staggered. The contact elements 212, 213 are connected to the housing 10, as at 218, 219, with the end of one element 212 extending beyond the end of the other. Thus arranged, the ends of the contact elements 212, 213 engage a respective one of the conductive elements 214, 215.

Accordingly, when the shaft 95 is rotated, each of the contact elements 212, 213 alternately engages the conductive elements 21.4, 215, but the conductive elements are engaged by only one of the contact elements 212, 213 in any position of the shaft 95.

The conductive elements 214, 215 are connected to the D-C source 124, as by respective brush contacts 220, 221 to ground, and through a connection 222 to the main on-0E control switch. When the switch is closed, and with the switch button 16 in the F or R position, motor 187 is driven in one direction in one position of the shaft 95, and in the opposite direction in the next succeeding position of the shaft 95.

The pawl plate 111 must be properly positioned so that the high speed motor 187 will effect successive movements of the shaft 95, and hence the heads 3032, in the proper direction. When the switch button 16 is in the F position, which characterizes movement of the heads 30-32 from the outer to the inner edge of the tape 24, the lever 121 is in the position to permit the lower pawl 117 to engage the pinion 108. Successive movements of the plunger 112 by the solenoid 110 thus effect clockwise rotation of the shaft 55 (viewed in FIGURE 15 to move the bracket 35 and the heads 30-32 in the same direction.

When the switch button 16 is in the R position, the lever 121 is moved to place the upper pawl 116 in position to actuate the pinion counterclockwise and effect successive movements of the heads 30-32 from the inner edge to the outer edge of the tape. Thus, by synchronizing the setting of the pawl plate 111 with the position of the switch button 16, the high speed motor is adapted to rapidly move the tape in either direction to any desired position.

The manual control for positioning the pawl plate 111 is illustrative only. Preferably, the position of this plate is effected automatically on movement of the switch button to either of the F or R positions. One means for such automatic positioning is illustrated in FIGURE 20, and includes a relay 225 for actuating a lever 121' connected to the plate 111. The lever 121' is adapted by a spring 226 to normally hold the plate 111 in a position wherein the lower pawl 117 will engage the pinion 108 when the solenoid 110 is energized to retract the plate 111. When the relay 225 is energized, the lever 121 is pivoted to a position where the pawl 116 will engage the pinion 108 when the plate 111 is retracted.

Thus, when the switch button 16 is in the F position, the pawl 117 for effecting forward movement of the heads 30-32 is in its normal position. When the relay 225 is energized, the pawl 116 is held in position for effecting reverse movement of the heads. To effect such positioning for reverse movement automatically, I utilize a switch having its switch arm 227 ganged with the switch arms 200, 201 of the F-R switch. The switch arm 227 is connected to the relay 225, as at 228, and is adapted, when the switch button 16 is moved to the R position, to connect the relay coil to ground, as through a connection 229; the other end of the relay coil is connected, as at 230, to the on-off switch. In the other positions of the switch button 16, i.e., neutral and F, the switch arm 227 is disconnected from the ground.

From the foregoing, it will be readily apparent that my invention embraces other mechanical and electromechanical means for properly positioning the pawls 116, 117 for actuating the pinion in the proper direction when the switch button 16 is placed in the F and R positions.

The above-described control for the high speed motor 187 is useful for quickly and positively moving the tape 24 so that the heads 30-32 are located on any desired track. If, for example, one is dictating and desires to play back material recorded on a track preceding that on which sound is presently being recorded, all he needs to do is move the switch button 16 to the R position. Thereupon the high speed motor 187 reverses the capstan drive and the heads 30-32 are shifted in the direction opposite to that in which they were moved while recording. The track is reached quickly in this manner, whereupon movement of the record-listen control switch to the play-back position permits the desired material to be reproduced.

My invention also incorporates additional means for quickly positioning the heads 30-32 on any desired track and for operating the capstan to place a specific portion of the tape on which track against the heads. To this end, an external positioning knob 231 is secured on one end of the shaft 95 (see FIGURES l-3). The knob 231 carries spaced members coresponding to the number of tracks for the heads 30-32. The knob 231 is used to turn the shaft 95 independently of the solenoid 110.

The housing carries an index mark 232, and the alignment of any number on the knob 231 indicates the track with which the heads 30-32 are aligned. Thus, to place the heads 30-32 on any desired track, all that is necessary is to turn the knob 231 to align the number representing such track with the index 232.

This selection can be made at any time and from any track position. For example, recording may have proceeded to the point where the heads 30-32 are on the tenth track, in which case the knob 231 will have rotated with the shaft 95 to a position where the numeral 10 is aligned with the index 232. If it is desired to move the 14 heads :back to the second track, the knob 231 is turned to align the numeral 2 with the index 232.

To identify the portion of the track which lies on the heads 30-32, the tape 24 is suitably numbered, and the cartridge casing 20 has view windows 234, 235 through which the numbers are visible. Each half of the tape is numbered (see FIGURE 22) so as to provide consecutively reading numbers regardless of the direction (right-to-left or left-to-right) in which the tape is moving. For example, a tape having an available recording length of thirty feet may have numbers 0-1000 (approximately each /s-inch apart) reading from left to right on onehalf of the tape, and the same numbers reading from right to left on the other half. The numbers may be placed on either surface of the tape, although if placed on the oxide surface, they would preferably be defined by oxide material which is of a color contrasting with the remaining oxide coating. Preferably, however, the numbers are imprinted on the nonsensitive or shiny surface, in which case the numbering can be done for relatively little expense.

The significance of numbering the tape as above explained will be seen upon noting that the direction of tape travel is related to the track on which the heads 30-32 are located, in terms of whether the track is an even-numbered track. For example, assume that the heads are initially positioned at the outside edge of the tape, so that they are moved toward the inner edge is recording proceeds, i.e., the outside track is track I. Also, assume that the tape is initially on the left-hand reel 21. The shiny or numbered side of the tape is visible through the windows 234, 235.

In the above-assumed condition, the start of the record cycle results in the capstan 25 moving the tape from left to right, with the sensitive surface passing over the heads 30-32. The numbers visible in the window 234 (see FIGURE 23), which read from right to left on the tape, are the numbers which appear in an increasing progression as they pass the windows 234 from left to right. The only time such numbers appear as an increasing progression is when the tape is traveling from left to right, i.e., transferring from the left reel 21 to the right reel 22. This event occurs only on the odd-numbered tracks 1, 3, 5, 7, 9, 11.

On the even-numbered tracks 2, 4, 6, 8, 10, 12., the tape travels from right to left. The numbers on the outer half of the tape, appearing in the window 235, appear in an increasing progression.

Thus, for forward movement of the tape, wherein the heads 30-32 are moved from the outer to the inner edges of the tape, the numbers in the windows 234, 235 which appear as increasing numbers are correlated with the tracks on which the heads 30-32 are located. Conversely, if the capstan 25 is reversed from its normal direction of rotation, as by moving the switch button 16 to the R or F position to operate the high speed motor 187, the numbers in the window identified with the track will appear as decreasing numbers.

From the foregoing, it will readily be seen that one can position the heads on any desired track, and then operate the motor 187 to quickly move the tape to a position wherein the heads 30-32 are located at a specifically identifiable portions thereof. Preferably, the windows 234, 235 are covered with magnifying lens elements, to insure that the numbers are readily observable when the inner end of the tape on the reel 21 is approached, i.e., when substantially all of the tape has been transferred to the right-hand reel 22.

My invention not only provides a unique dictating machine for ofiice use, but is uniquely adapted to the recording of music. For example, by providing a tape length sufficient to record an entire piece on one track, e.g., 2.5 minutes playing time for popular songs and music, a cartridge is provided which contains a plurality of songs, one on each track. For example, a tape having twenty tracks contains twenty recorded songs. The total volume of such a cartridge is less than ten cubic inches, which is in sharp contrast to a stack of ten 7-inch disc records (each having one song recorded on each side), which occupy a total volume between 30 and 40 cubic inches.

Furthermore, the problems involved in handling conventional disc records, as by placing them on the turntable for playing a song on one side, then turning them over to play the song on the other side, and also the attendant risk of damage to the playing surfaces, are all non-existent in my invention. After the tape is initially assembled in the cartridge, there is no further handling of it in recording or reproducing. A label provided on the cartridge lists the tracks by number and the titles of the pieces recorded on the respective tracks. On plugging the cartridge into place, the selection of a desired number is simply made by turning the knob 231 to align the desired track number with the index 232. Then the record-listen switch is placed in the listen position, and the start-stop switch 14 is actuated to start the tape. At any time, of course, the

start-stop switch 14 may be actuated to decouple the capstan drive connection.

On the other hand, if it is desired to play all of the numbers, this will automatically be accomplished by setting the knob 231 on track 1. Actuating the startstop switch 14 to start the capstan turning effects playback of all pieces on the tracks in succession.

The foregoing described feature for track selection makes possible the provision of juke box music constructions of amazingly small size. For example, a tape 24 several inches wide (e.g., 5 inches) may be employed, on which are recorded one hundred songs, one to a track. A control knob 231' (see FIGURE 25) having members 1400 thereon is releasably held by control means 240 which is adapted to release the knob 231 for rotation upon inserting a coin therein, as through a coin slot 241. The numbers on the knob 231 identify tracks on which specific pieces shown on an accompanying label (not shown) are recorded. The desired selection is made by aligning the proper track number with the index 232'.

For a wide tape, I prefer to use a sprocket drive. To this end, and referring to FIGURE 23, a capstan 25 having sprocket teeth at its ends is employed, and the tape 24 is provided with sprocket holes at its edges. Such a drive is conventional of course. With such a sprocket drive, I provide a narrow slot 128' in the edge of the tape adjacent each end, so that the .metal portion 129 of the capstan 25 will be exposed for engagement by the contact 126 to effect reversal of the capstan drive.

Since the coin-operated control means 240 is used for reproduction only, only a loudspeaker is needed, i.e., the record amplifier and microphone are eliminated, and the device is always connected to effect reproduction. Also, the erase heads 31., 32 and erase current source 135 are eliminated.

The control means 240 also controls the starting and stopping of the normal tape drive, and for this purpose may include a conventional timing mechanism (not shown) to maintain such condition of operation for the allowable playing time, e.g., the time for the entire length of tape to pass over the head on the selected track, and to stop the operation at the end of such period.

It may be necessary to delay normal tape drive and reproduction where a selection requires that the tape first be transferred from one reel to the other. For example, the tape may be located on the left-hand reel 21, as for movement from left to right for reproducing songs on an odd-numbered track. If one elects to play a number recorded on an even-numbered track, it is necessary first to transfer the tape to the right-hand reel 22 before playing begins. The operation of the high speed motor 187 and the starting of the reproduction must be synchronized so that the motor 187 is first operated to quickly transfer the tape to the right-hand reel, and then the start-stop 16 switching mechanism is actuated to effect reproduction of the selected recording.

Similarly, if material on an odd-numbered track has been previously reproduced, so that the tape at the end of such reproduction is located on the right-hand reel 22, the subsequent selection of an odd-numbered track requires that the tape first be transferred to the left-hand reel 21.

The last setting of the knob 231 provides the necessary indication of whether the tape must be transferred. Suitable instructions on the operation of the device disclose to one making a new selection that if an odd-numbered track number is aligned with the index, any number selected on an even-numbered track will automatically be played on inserting a coin in the slot 241; but if a number on another odd-numbered track is to be selected, the reverse control switch 16 will first have to be actuated for transferring the tape back to the left-hand reel 21. Similarly, if the last piece played is indicated by the knob 231' as having been an even-numbered track, and

another even-numbered track is being selected, the reverse control switch 16 must first be actuated for transferring the tape onto the right-hand reel before reproduction will start. Gauging of the start-stop and reverse control switches 14, 16 aids in preventing operation of the capstan from the normal drive motor 60 until the tape has been transferred.

It will be seen that the transfer of tape when necessary may be effected automatically, and that my invention embraces the use of such cooperative control means.

If desired, recording on each track may be started in every case with the tape on one reel, e.g., the lefthand reel 21.. The reproduction will thus require, in every instance, transfer of the tape back from the right-hand reel 22 to the left-hand reel 21. To accomplish this automatically, the solenoid is adapted to actuate the reverse switch 16 at the end of each track; in this case, only the end of the tape secured to the left-hand reel 21 is adapted to expose the metal portion of the capstan for actuating the solenoid. A suitable timing mechanism (not shown) for the motor 187 automatically stops it when transfer of the tape to the left-hand reel 21 is completed. Thus, for each selection, the unit is always conditioned for reproduction upon inserting a coin.

The above described reproducer will be seen to be extremely simple and compact, in sharp contrast to the elaborate and expensive automatic controls and bulky, heavy apparatus required for selecting and manipulating disc records for reproduction in conventional juke boxes.

Other features of my invention reside in details of construction and arrangement of the parts thereof. One such feature resides in a simple locking lever 250 (FIG- URES 1 and 3) on the housing 10 for releasably securing the cartridge 11 in place when it is plugged in. The lever 250 is pivoted on the housing, as at 251, and has a finger 252 on its inner end which is received in an opening 253 in the cartridge casing 20. When the cartridge is located on the housing, the lever 250 is moved to a position when the finger 252 locks against the inner surface of the panel 39, thereby to hold the cartridge firmly in position.

Another feature is the provision of parallel rods 255, 256, 257 (see FIGURE 3) extending the width of the tape along the bottom of the cartridge 11. As shown, the rods are located in aligned notches in the front and rear panels of the cartridge, with the axis of the center rod 256 being slightly lower than the axes of the other rods 255, 257. These rods are so spaced that the erase heads 31, 32 bear against the tape 24 with equal pressure. The heads 3032 are disposed along an are, as will be seen by inspection of FIGURE 3. The left-hand erase head 31 is positioned between the capstan 25 and the left rod 255; the record-listen head 30* is located be- 17 tween the rods 255, 256; and the erase head 32 is located between the rods 256, 257.

As seen, the heads when positioned in engagement with the tape force the tape inwardly slightly. Since the tape is under tension at all times, this arrangement insures that the tape is always biased against the heads, thus providing the necessary firm sliding engagement, as for maximum efiectiveness of the head 30 in recording and playback operations, and of the erase heads in effectively demagnetizing the tape ahead of the recording.

The heads 30-32 are held in position by means of a latch member 258 on the housing which engages the bar 33 in which the heads are embedded. When it is desired to remove the cartridge, the latch 258 is moved to permit the bar 33 to be pivoted away from the tape. Release of the cartridge from the housing, by movement of the lever 250 out of locking engagement therewith, permits its removal without dragging the tape along the heads.

It is, of course, not desirable, to record in any other situation than where the switches 136-138 are in the record position. In addition to the described disengagement of the erase current source 135 during reproduction, I also provide interlock means for preventing recording and/or erasing during operation of the highspeed motor 187. Referring to FIGURE 20, this safety feature is provided by switches located in the leads 143, 162, 163, wherein the switch arms 260, 261, 262 are ganged with the switch arms 200', 201, 227. The switch arms 260-262 are adapted in only the neutral positions of the switch arms 200, 201, 227 to connect the respective heads 30, 31, 32 to the heads 143, 163, 162.

I also provide positive positioning means for locating the heads 36-32 in the center of the tracks to which they are moved by the action of the shaft 95. The locating means (see FIGURE 11) comprises a star wheel 265 secured to the shaft 95, and a detent arm 266 which is pivotally mounted on the housing 10, as indicated at 267. The arm 266 at its lower end is connected to a spring 268, which constantly urges the upper end of the arm toward the star wheel 265. The upper end of the arm 266 carries a pin 269 which engages the star wheel 265.

The periphery of the wheel 265 is formed of spaced teeth, the sides of which meet to form slightly curved troughs 270. With this construction, the pin 269 is forced by the spring 268 to the center of the trough 270 between adjacent teeth. This position of the pin corresponds to the center of a track, and the spring 268 exerts enough force so that, if the shaft 95 were to be turned, as by operating the knob 231 or solenoid 110, only to a position wherein the pin 269 was positioned on the side of one of the teeth, the force of the pin causes the shaft 95 to rotate further until the pin is centered between the teeth. However, the shaft 95 readily turns against the pin when actuated by the solenoid 110 or knob 231. When this happens, the pin rides along and over the teeth of the wheel 265. But when direct operation on the shaft 95 ceases, the detent 266 and spring 268 cooperate to insure that the shaft will be held in a position where the heads 30-32 are centered on a track.

For manual start stop control, I provide an externally operable pull bar 272 (see (FIGURES 1, 2 and 18) which is secured at its inner end to the plate 168. The outer end of the bar 272 rides in a slot 273 (see FIG- URE l) which at its rear end curves downwardly and forwardly. To move the plate 168 to the stop position, where the motor 187 is brought into driving connection with the drive wheel 78, the bar 272 is pulled rearwardly so that the end thereof moves into the forwardly inclined portion of the slot 273. The end of the bar 272 is thus latched, thereby to hold the plate 168 in the retracted position. Unlatching is effected by simply moving the end of the bar 272 upwardly to the horizontal portion of the slot 273, whereupon the plate 168 and bar 272 are moved 18 to the normal forward position by the action of the springbiased plunger 167.

By virtue of my moving the tape at a constant speed (determined by the speed of rotation of the capstan) and the frictional engagement between the capstan and the tape, there is no problem of slippage between the capstan and tape during high speed operation. Furthermore, there is no problem of slippage or of continued movement of the tape upon stopping the high speed motor. Immediately upon stopping the motor, the capstan (and hence the tape) comes to rest. It is this feature which makes it possible to rapidly and accurately position any portion of a track adjacent the heads.

For high speed forward or reverse movement, transfer of the tape from one reel in my compact cartridge takes place much faster than is possible with prior art apparatus. For example, a 30-foot length of tape can be transferred in a matter of twenty seconds or less, which of course is at a much lower capstan speed than would be possible or practical in prior art mechanisms.

The normal tape speed, for recording and playback, may be any of the conventional speeds, i.e., 1% inches per second, 3% inches per second, 7 /2 inches per second, or any other speed practical for recording particular types of sounds. Further, it will be appreciated that my invention embraces means for selectivley operating the drive wheel so that the capstan will move the tape at any of the desired speeds.

It should be noted that the same arrangement of the earns 96, 97 for controlling the drive connection to the drive wheel 78 upon each shift of the heads 30-32, and the same rack 101 and pinion 100, can control such connections and shifting in synchronism regardless of the number of positions the heads can be placed in. For a particular configuration of the cams 96, 97, and number and spacing of teeth on the rack and pinion, the number of positions to which the rack (and hence the heads 30-32) can be shifted is determined. To use these same elements where a greater number of positions of the heads is desired, all that is necessary is to employ a reducing gear, not shown) between the pinion 100 and the rack 101.

Referring to FIGURE 26, there is shown a housing 310 that includes a motor casing 311 mounted on a support base 312, and an elongated cover element 313 hinged to the motor casing 311, as at 314. The cover element 313 encloses a driving mechanism, tape supporting mechanism, and magnetic heads which are supported on the base 312. For operating the drive mechanism and effecting recording and reproducing operations, a record-listen control lever 318 is provided that extends through a slot 319 in the cover 313. The housing 310 includes a portion 320 that houses suitable microphone and loudspeaker elements, together with electronic control means by which to provide the requisite power for recording sounds on tape or reproducing sounds recorded on the tape. A mesh screen 321 is provided in the housing portion 320 through which sounds pass to actuate the microphone and from which sounds emanate from the speaker. The entire unit can be fitted into a mans coat pocket. Yet, despite such small size, the unit has as much (or more) playing time as can be obtained with conventional recorders using 7-inch diameter reels for carrying 1,200 feet of magnetic tape.

Other controls accessible from the exterior of the cover element 313 include a lever 325 extending through a slot 326 for controlling the direction of movement of the magnetic tape. Also, to indicate visually the line along the tape at which the magnetic heads are positioned, the cover element 313 is provided with an opening 327 through which to view a fixed index 328 and the peripheral portion of an angularly movable disc 329. The disc 329 is provided with spaced numbers adjacent its periphery, and is arranged so that the number thereon aligned 

1. IN COMBINATION WITH A LENGTH OF MAGNETIC TAPE HAVING ITS ENDS SECURED TO A PAIR OF REELS, AND A TRANSDUCER TO BE MOVED TRANSVERSELY OF THE TAPE, A TAPE DRIVE AND TRANSDUCER POSITIONING CONTROL SYSTEM COMPRISING: A UNIDIRECTIONAL MOTOR HAVING AN OUTPUT SHAFT; SHAFT MEANS TO BE COUPLED TO SAID OUTPUT SHAFT FOR DRIVING SAID REELS AND TAPE; COUPLER MEANS ROTATABLE BY SAID OUTPUT SHAFT FOR COUPLING SAID SHAFT MEANS TO SAID OUTPUT SHAFT, SAID COUPLER MEANS BEING MOVABLE BETWEEN TWO POSITIONS WHEREIN IT CAUSES SAID SHAFT MEANS TO ROTATE IN OPPOSITE DIRECTIONS; AN ELONGATED RACK MEMBER CARRYING SAID TRANSDUCER AT ONE END THEREOF; A PINION MEMBER ENGAGING SAID RACK AND ROTATABLE TO IMPART LONGITUDINAL MOVEMENT TO SAID RACK MEMBER; CAM MEANS FOR MOVING SAID COUPLER MEANS BETWEEN ITS TWO POSITIONS; AND A ROTATABLE CONTROL SHAFT MECHANICALLY COUPLED TO SAID PINION MEMBER AND CAM MEANS, SAID CAM MEANS BEING OPERABLE TO CAM SAID COUPLER MEANS ALTERNATELY BETWEEN ITS TWO POSITIONS A PLURALITY OF TIMES DURING A REVOLUTION OF SAID CONTROL SHAFT. 